Instrument for centering purposes.



1 A. DENBS.

INSTRUMENT FOR CENTBRING PURPOSES. APPLICATION FILED APB..16, 1912.

` 1,038,729. Patented Sept. 17, 1912.

nLAnA'a DENES, or BERLIN, GERM nur, Assienoa 'roimx msnen, or BERLIN,

GERMANY.

INSTRUMENT FOB CEIN'.ITIIIING'V PURPOSES.

item29.

Specification of Lettersatent. Patented Sept. 17, 1912.

Applicationl filed A911116, 1912. Serial No. 691,226.

. i( i Y 1 0 at7 whom zt may concern:

I 'Be it known that I, ALADR DNEs, subj'pct of the Kingof Hungary, residing at 14 Landsberger Allee, Berlin, Germany, have invented certain new and useful Improvements in Instruments for Centering Purposes, of which the following is a specification.

This invention relates toa-n instrument for centering blanks or marking the center of circular holes in order to have the' blanks indexed to suitthe adjustment in machine working.

Referring to the accompanying drawing, Figure 1 is a plan view of the instrument, Fig. 2 a cross-section on line A B of Fig. 1 viewed in the direction of the arrow b, Fig. 3 a cross-section on line G D of Fig. 1 viewed in the direction of the arrow d and Fig. 4 shows a modification of the instrument. Figs. 5 and 6 are sections on line E,

Fand G, H of -Fig. 4.

The slide casing 1 (Figs. L3) carrying two pins 3 and' 5 is constructed as a guide iframe formed with suitable tracks along which the slide 2 is movable by hand. The inner slide or rule 10 is also arranged to slide axially along the casing or frame 1 and is provided with the center mark 0. Itis automatically moved on its guiding track through the medium of a ear 6, 7 referred to later on. mark c is the medial perpendicular of the connecting line between the pins 3 and 5 provided on the frame 1. A gear composed of a pair of pinions 6 and 7 engaging with racks 8 and 9 respectively is pivotally mounted on the slide 2, the pivot 11 serving or'both pinions 6 and 7 united together. During the longitudinal adjustment of the slide 2,the pinion 7 takes up the rolling motion from the rack 9 fixed to the frame 1 and this motion is imparted to the sliding rule 10 by means of the pinion 6 gearing with the rack S and having the gearing ratio of 1:2 with respect to the pinion 7. The rack 8 is secured to the movable rule 10. The slide 2 carries one or two pins.4, 4 arranged ,as counterparts to the pins 3 and 5 of the frame 1. By the operative connection of the parts, the effect is attained that the movement or adjustment of the rule 1() takes place at half the speed or ratio of the slide 2 when moved by hand, so that the position of the center mark c halves the distance between the pins The track line of the center 3 and 5Honthe frame 1 and the pin-or pins 4 on. thevslide 2. The pins 3, 5 and 4 in any whose true center is given by the center mark c. This latter may be provided with a centering hole 13 (as shown in Fig. 3) or adapted to serve otherwise as centermark.

When it is intended to use the apparatus, it should be placed uponthe blank or work, the two pins 3 and 5 on the frame should abut. agamst the peripheral contour of the circular hole or body and the slide 2 moved so far until pin 4 abuts against the opposite side of thel periphery, whereupon the parts are fixed by means of the set screw 12, the center mark c then pointing to the center of three or four pins.

Fig. 4 shows similarly to Fig. 1 a modified arrangement of the instrument. A different gear mechanism is substituted for the pinions 6, 7 and consists ofpinions 15, 16, 17 arranged in such a manner that the inter' mediate pinion 15 intermeshes with the rack 19 oi' the frame 1 and that the pinion 16 is driven by the said intermediate pinion 15 pinion 17 engaging with the rack 1.8.4 In this case, too, the gearing ratio is 1:2 'and the respect to the peripherali contour determined or encompassed by the pins.

Having now particularly described and ascertained the nature oil-my said invention and in what manner the same is to be performed, I declare that what I claim and wish to secure by Letters Patent is 1. In an instrument of the character specified, the combination with 4a guide frame provided with means for engagingthe erelatively to vsaid frame and providedl with means for engaging the periphery ofan'object, a center mark movable in `said frame,

center mark one half the distancemoved by said slide.,

2. In an instrument of the character specified, `the combination with a guide frame provided with Xed means for engaging the peripheryof an object, of a slide ad]ustable, in said frame and provided with means for engaging the periphery of an object at a point opposite said fixed means, a slide rule provided with a center mark, and gearing the circle determined or encompassed by the center mark c is automatically centered with' and meansfor automatically moving said position determine the periphery of a circle, l

so as to impart the motion to the associate l riphery of, an object, ofa slide adjusta' le 'p operable by the movement of said slide for moving said slide rule and center mark one half the distance moved by said slide.

3. In an instrument of the character specilied, the combination with a guide frame provided with means for engaging the periphery of an object, of a lslide adjustable in said frame and rovided with means for engaging the periphery of an object, a slide rule provided with a center mark, a gear member carried each by the frame and the slide rule, and complementary gear members carried by said slide whereby, upon movement ofthe latter, the slide rule and center mark are moved one half the distance moved by the'said slide. v

4. In combination with a centering instrument, a track forming frame, a slide adjustable by hand and guided along the said frame, both frame and slide being provided `20 vvitli suitable symmetrically disposed abut ting pins, a rule `adapted to slide and to, be adjusted along the frame and carrying the center mark, a gear connected with Jhe slide and having its pinions intfrmeshing with 25 ALADR DENES.

. Witnesses: l f

WGLDEMAR HAUPT, HENRY HASPER. 

